The present invention relates to container-carrying railroad freight cars, and in particular relates to container-supporting structures located in the corners of a container well of such a railroad car unit.
Railroad cars including deep side sills defining container wells have been used for a number of years to carry intermodal cargo containers stacked in two tiers, with a pair of short containers loaded end-to-end in the container well, or a standard container such as a 40-foot long container carried in the well, and with a second-tier container at least 40 feet long carried on top of the container or containers in the well. Such cargo containers are built to a standard width, typically 8 feet, which must be accommodated between the side sills of the car that define the container well.
The containers in the well are supported at each end of the well by container support structures that, in one type of container car, have previously been built in the form of weldments of cut and bent steel plate welded to the lower portions of the side sills of the car. Such cargo container support structures have been undesirably expensive to build because of the amount of skilled labor required to weld the various parts together. Such welded assemblies also include surfaces that are difficult to reach for cleaning and preservation of the metal during the life of such a car. Some of the welds required to assemble the previously utilized cargo container support assemblies have been located where welds of the required quality are difficult to accomplish, and production costs are consequently higher than is desired.
What is desired, then, is an improved container carrying railroad freight car in which cargo container support structures are less expensive, more reliable, and lighter in weight than the previously utilized fabricated container support assemblies.